Eventually, the world will run out of fossil fuels to fuel our cars, the electricity in our homes, all technology, so what are we going to use in place of fossil fuels? Well, as disgusting this sounds, you can use human urine (pee) as a power source. In 2013, a group of researchers at Bristol Robotics Laboratory in the UK proved that they could power a cellphone with human urine. They used MFCs (microbial fuel cells) to generate enough energy for a smartphone to make short phone calls, text, and do some web-browsing. MFCs are energy converters that use bacteria found in nature to breakdown organic matter, producing electrons that are converted into energy. The more waste the microbes consume, the more energy the system can generate and for longer.
 
Another way to convert human urine into energy is through microbial electrolysis. Urine is made up of about 98% water and 2% urea, which is made up of carbon, oxygen, nitrogen, and hydrogen atoms. A researcher created the GreenBox which uses microbial electrolysis to extract the hydrogen from the urea. Electrolysis uses an  electrical jolt to split the urea into hydrogen and oxygen atoms, then captures the hydrogen to produce energy. The nitrogen can be used for artificial fertilizers.

So can pee really be used for powering future generations? Yes, but there are some obstacles along the way of being able to do that. There's the costs of performing this process. This way of producing energy is still developing, but think about it, it actually can be useful. Now all we have to do is eliminate the odor!

Reference:
http://www.bbc.com/future/story/2014031 … y-possible